Anxiously awaited follow-up observations with NASA's Hubble Space
Telescope have confirmed the presence of two new moons around the
distant planet Pluto. The moons were first discovered by Hubble in
May 2005, but the science team probed even deeper into the Pluto
system last week to look for additional satellites and to characterize
the orbits of the moons.

Though the team had little doubt the moons are real, they
were happy to see the moons show up very close to the locations
predicted from the earlier Hubble observations. The initial discovery
is being reported today in this week's edition of the British science
journal Nature.

The confirmation reinforces the emerging view that the Kuiper Belt,
a swarm of icy bodies encircling the solar system beyond Neptune,
may be more complex and dynamic than astronomers once thought.
Pluto resides inside the Kuiper Belt and is about 3 billion miles
from the Sun. Pluto was discovered in 1930.

The moons' orbits are in the same plane as the orbit of the much
larger satellite Charon (discovered in 1978). This likely means the
moons were not captured, but instead were born, along with Charon, in
what is commonly theorized to have been a titanic collision between
two Pluto-sized objects over 4 billion years ago.

A team of astronomers, led by Hal Weaver of the Johns Hopkins University Applied
Physics Laboratory in Laurel, Md., and Alan Stern of the Southwest
Research Institute in Boulder, Colo., made the new observations on Feb.
15, 2006, with Hubble's Advanced Camera for Surveys (ACS).

The team used the sharp vision of the ACS to do a targeted search of the
region around and inside the orbits of the twin moons. In addition to
confirming the reality of the new moons, the observations also rule out
the possibility of other satellites of roughly similar size orbiting Pluto
inside the orbits of the two moons. The moons, provisionally designated
S/2005 P 1 and S/2005 P 2, are approximately 40,000 and 30,000 miles away
from Pluto, respectively.

Astronomers believe that the formation of the Pluto system is similar to
that of our Earth and Moon. In both cases a comparable-sized body slammed
into the parent planet. Simulations show that debris from the collision
would go into an orbit around the planet and coalesce to form one or more
satellites. Investigating how Pluto ended up with three moons while the
Earth has only one should yield valuable insights into the processes by
which satellite systems form around planets.

The team will use Hubble again on March 2 to study the new moons. They
hope the follow-up observations will provide information on the moons'
color, as well as their size and shape, which could yield further clues
about the formation and evolution of the Pluto system.

In the Hubble image, Pluto is in the center and Charon is just below it.
P 1 is to the right and just below Charon. P 2 is to the right of Pluto
and Charon.

The Pluto System on Feb. 15, 2006 (Non-annotated)
Astronomers using NASA's Hubble Space Telescope have confirmed the
presence of two new moons around the distant planet Pluto. The
moons were first discovered by Hubble in May 2005, but the Pluto
Companion Search team probed even deeper into the Pluto system
with Hubble on Feb. 15 to look for additional satellites and to
characterize the orbits of the moons. In the image, Pluto is in
the center and Charon is just below it. The moons, provisionally
designated S/2005 P 1 and S/2005 P 2, are located to the right of
Pluto and Charon.

The Pluto System on Feb. 15, 2006 (Annotated)
Astronomers using NASA's Hubble Space Telescope have confirmed the
presence of two new moons around the distant planet Pluto. The
moons were first discovered by Hubble in May 2005, but the Pluto
Companion Search team probed even deeper into the Pluto system
with Hubble on Feb. 15 to look for additional satellites and to
characterize the orbits of the moons. In the image, Pluto is in
the center and Charon is just below it. The moons, provisionally
designated S/2005 P 1 and S/2005 P 2, are located to the right of
Pluto and Charon.